ANALYTICAL APPARATUS AND SYSTEMS

摘要

Sensor devices and analytical method using a permeable liquid layer on a sensor surface so that analyte from an external medium can enter the liquid layer and reach the sensor (2) by diffusion. The sensor may be secured within an open-ended tube (1) through which the liquid for the layer is fed in and regulated to maintain required conditions around the sensor. The outward liquid flow (5) maintains sensor activity and allows adjustable control, e.g. through choice of tube configuration and/or sensor position. The liquid for the layer can be fed in at an appropriate part of the tube and may be integral with the main tube. The sensor may be conventional, especially an electrode, and preferably is supported independently within the tube but may be an active sensing area within the tube rim. These arrangements avoid unacceptable dilution of media being examined, especially for monitoring biological media and environments.